HT813 FXO not switching to T.38


I am attempting to use an HT813 to send faxes from a Brooktrout based server (RightFax) through a PSTN phone line. The problem I have is that the HT813 never switches from G711 to T.38. Any ideas? (T.38 is enabled on the FXO port, and reinvite is enabled as well.)
Edit: To make things a little clearer, the Brooktrout is a SIP client. I am trying to out through the FXO port to the PSTN.


Without packet log i doubt anyone can help.
We need know what happens.

#3 (204.6 KB) (10.0 KB)
Packet capture and syslog from the ht813


So the BT device is connected to the HT’s FXS port, correct?


No. The Brooktrout is a SIP client. If I set it for G.711 fallback it works fine. When set for T.38 only the HT never switches. (I have since tried other T.38 software clients with the same result.)


To be honest i do not see any indication for trying T.38 as well. There is no much option in HT so i guess it set ok
It can be bug, maybe you should try GS ticket ?


I opened one about the same time I posted this, hoping someone had done it before. Still no resolution. Fortunately the path from the computer to the HT is Gigabit Ethernet, so G.711 is working well for now.


G.711 use 256 kb top, so really 10MBit is enough :slight_smile: